Im looking to improve my Vega cosplay, and one of the big things that I feel is a problem with it currently is my body paint. I just used cheap party city stuff for NYCC since I didnt have enough time to research and have something shipped to me. It actually looked good when I applied it, but once people start sweating and bumping into each other it flaked off pretty quick. I was able to get a makeup artist at the con to touch it up with alcohol based paint which was awesome because it didnt come off and she connected the back for me (I painted myself with a brush and couldnt reach all of my back).

Im not totally sure if I should go with water based paint or alcohol based paint, so I was thinking I would try one of each so I can get a feel for em and see which I like better. For water based I was thinking this: http://www.mehron.com/Paradise_Makeu...onal_p/800.htm (maybe the Wild Orchid color), and for alcohol based I was thinking this: http://www.mehron.com/Paradise_Makeu...onal_p/800.htm (maybe spring for the platinum version or Purple or one of the specialty colors like Rigor Mortis).
Am I on the right track with these paints? Are there any other things I would need to buy to make this work?

The other question I have is how much paint do I actually need? The only body paint necessary for this cosplay is for the snake tattoo that wraps around the body, so how many ounces would do that job once? twice etc? Thanks in advance for any help!

I'm not familiar with that brand, hopefully someone who is will come in and weigh in on it. Most people I know (including myself) use Ben Nye or Kryolan for body paints/makeups.

However, I can help with the latter questions a bit. It looks like the tattoo covers a relatively big area, but one of the "professional size" (1.4 oz) ones you have linked should be enough for several applications, at least twice, but I'd bank on more than that. (There's a review on it were someone claims they used one to cover their entire body.)

Additionally, you're going to need a sealant. I know that Ben Nye and Kryolan both make them, and the brand that you've linked probably does too. They come as powders or sprays, both of which work about equally, it just comes down to personal preference. (Note: If you get a powder, white is recommended for vibrant colors, but I find that flesh-tone powders over vibrant colors make them look more like real tattoos, so again, personal preference. The sprays are clear.)